BACKGROUND OF THE INVENTION
This invention relates to a disc cartridge, and more particularly to a disc
cartridge having a disc-like medium such as a recordable/reproducible optical disc, a
magneto-optical disc or the like rotatably received in a casing.
In general, information media including, for example, a disc-like medium such
as a magnetic disc, an optical disc, a magneto-optical disc or the like are each used in the
form of a disc cartridge while being received in a casing formed by joining upper and
lower casing members to each other. The disc cartridge includes a shutter for selectively
opening or closing holes such as head insertion holes, drive shaft insertion holes and the
like formed through the upper and lower casing members of the casing. Generally, such
a conventional disc cartridge is not provided with any means for taking out the disc-like
medium from the casing for replacement. However, a disc cartridge called a CD caddie
which is used for a CD-ROM or the like is constructed so as to permit a CD to be taken
out of a casing. Such a CD caddie is adapted to be used in a CD-ROM reproducing unit
of the type of using the CD caddie. Thus, the disc-like medium is used either in the form
as taken out from the disc cartridge or in the form as received in the disc cartridge
depending on the type of a recording/reproducing unit, thus, it is needed to take out the
disc-like medium from the disc cartridge as required.
However, the conventional disc cartridge including the disc-like medium
takeout mechanism is not constructed so as to permit a shutter mechanism to be
arranged on a side of the disc cartridge on which the disc-like medium takeout cover is
pivotally arranged. Also, upper and lower casing members of the casing of the disc
cartridge are rendered highly different in configuration from each other. Thus, the disc-like
medium takeout mechanism fails to be applied to a disc cartridge of the vertically
reversible type or both-sided type. Another disc-like medium takeout mechanism has
been also proposed which is constructed so as to open only a side surface of the casing
opposite from the shutter to take out the disc-like medium from the disc cartridge. The
proposed disc-like medium takeout mechanism causes the disc-like medium takeout
cover to be operated either detachably or pivotally. Detachable operation of the cover
leads to separation or removal of the cover from the casing, resulting in the cover being
possibly lost. Pivotal operation of the cover causes the cover to be engaged with the
casing through only a pivot shaft, so that the cover, casing or pivot shaft may be broken
due to application of a shock or external force to the disc cartridge. Also, it fails to fully
close the cover due to inclination thereof, leading to a deterioration in reliability.
In addition, the conventional disc cartridge equipped with the disc-like medium
takeout mechanism is provided with a disc-like medium takeout cover, which is arranged
on the casing of the disc cartridge so as to be pivotally moved for taking out the disc-like
medium from the disc cartridge, so that erasure prevention is carried out only by a lug
provided on an opposite side of the casing remote from the cover. Thus, once the lug is
removed from the casing, it is required to apply an adhesive tape or the like to a portion of
the casing from which the lug was removed, in order to carry out recording on the disc-like
medium again. Unfortunately, this renders handling of the disc cartridge troublesome and
causes an adhesive of the adhesive tape and/or the adhesive tape per se to be left on the
recording/ reproducing unit, to thereby possibly cause a failure or malfunction of the
unit.
Whereas, in the conventional disc cartridge which is constructed so as not to
permit replacement of the disc-like medium, an erasure prevention member is arranged
so as to be movable between a recordable position and a unrecordable position in the
casing, as widely known in the art. Application of such arrangement of the erasure
prevention member to the cover-equipped disc cartridge renders takeout of the disc
impossible or causes the erasure prevention member to be removed or detached from
the casing when the cover is open, because such a disc cartridge is generally constructed
so that the erasure prevention member is arranged at a disc takeout section.
Also, the conventional disc cartridge equipped with the disc-like medium
takeout mechanism lacks a detection mechanism for detecting whether the disc-like
medium takeout cover has been opened in order to take out the disc-like medium from
the disc cartridge in the past. When the disc-like medium is used as taken out from the
disc cartridge, there is possibility that a fingerprint, dust or the like is adhered to a surface
of the disc-like medium or the surface thereof is damaged, leading to an error such as
wrong recording, a failure in recording or the like during recording operation, resulting in
reading-out of data from the disc-like medium being failed. In order to avoid such a
problem, it would be considered to verify a recording section of the disc-like medium to
inspect the disc-like medium, to thereby check any possible error on the disc-like medium
before the recording operation. However, application of such a system to recording onto
the disc-like medium which has not been taken out from the disc cartridge causes a
length of time required for the recording to be double or more, resulting in being
impractical.
In view of the problem, a system has been proposed wherein a discrimination
section for detecting whether takeout of the disc-like medium has been carried out in the
past is arranged which is constructed so as to vary from an initial state and be never
permitted to return to the initial state when the disc-like medium takeout cover has been
opened even once. Thus, the system, so long as the cover has never been open, permits
the recording to be accomplished with an increased speed because it is not carried out to
verify the disc-like medium. Also, after the cover has been open, the disc-like medium is
subjected to verification although the verification requires time for the recording, resulting
in the recording being substantially free from any error.
Nevertheless, the conventional disc cartridge requires a troublesome
procedure that a user operates the discrimination section and then open the disc-like
medium takeout cover. Also, it causes debris produced from the discrimination section of
the disc cartridge to enter the casing of the disc cartridge, leading to damage to the disc-like
medium. Further, the debris possibly intrudes into the recording/reproducing unit,
leading to a failure or malfunction of the unit, resulting in deteriorating both operability and
reliability of the unit.
SUMMARY OF THE INVENTION
The present invention has been made in view of the foregoing disadvantages
of the prior art.
Accordingly, it is an object of the present invention to provide a disc cartridge
which is capable of readily accomplishing takeout and insertion of a disc-like medium with
respect to the disc cartridge while ensuring easiness of assembling thereof and increased
reliability in operation thereof.
It is another object of the present invention to provide a disc cartridge of the
double-sided operation type
in which both upper and lower sides thereof are formed with substantially the same
configuration, resulting in ensuring double-sided operation thereof while facilitating
takeout and insertion of a disc-like medium with respect to the disc cartridge.
It is still another object of the present invention to provide a disc cartridge
which is capable of repeatedly selecting erasure prevention or recordability on a disc-like
medium irrespective of arrangement of a disc-like medium takeout cover on the disc
cartridge.
It is even another object of the present invention to provide a disc cartridge
which is capable of preventing an erasure prevention member from being removed or
detached from disc cartridge due to operation of a disc-like medium takeout cover.
It is yet another object of the present invention to provide a disc cartridge which
is capable of detecting whether takeout of a disc-like medium has been carried out in the
past, to thereby exhibit increased reliability in operation thereof, facilitate handling thereof
and eliminating any malfunction thereof while keeping the disc-like medium or a
recording/reproducing unit from being damaged.
In accordance with the present invention, a disc cartridge is provided. The disc
cartridge generally includes a casing including an upper casing member and a lower
casing member joined to each other and formed with openings through which a
recording/reproducing head and a drive shaft are inserted into the casing, a disc-like
medium rotatably received in the casing, and a shutter arranged on the casing for
opening and closing the openings. The casing is formed on a side surface thereof
opposite from the shutter with a takeout opening which permits the disc-like medium to be
taken out of the casing therethrough. The disc cartridge further includes a cover slidably
and pivotally arranged on the casing to open and close the takeout opening, a guide
means arranged on one of the upper and lower casing members for slidably and pivotally
moving the cover, and an engagement member provided on the cover and engaged with
the guide means, to thereby be guided by the guide means.
In a preferred embodiment of the present invention, the cover is slidably and
pivotally arranged on one of the upper and lower casing members and has support shafts
provided on opposite sides thereof. One of the upper and lower casing members is
provided with guide grooves in which the support shafts of the cover are slidably and
pivotally fitted, respectively, to thereby permit the cover to be selectively opened while
being separated from the other of the upper and lower casing members.
In a preferred embodiment of the present invention, the support shafts of the
cover are each formed with a partially cut-out cylindrical shape, to thereby have a flat
surface partially formed on a periphery thereof, and are each fitted in a respective one of
the guide grooves so as to slide while the flat surface of the support shaft is guided along
a side surface of the guide groove. The guide grooves are each formed at one end
thereof with a circular hole, and the support shafts are each pivotally moved in the circular
hole of a respective one of the guide grooves, resulting in the cover being selectively
opened as desired.
In a preferred embodiment of the present invention, the cover is provided with
a receiving section for receiving an erasure prevention member and the erasure
prevention member is slidably held in the receiving section of the cover.
In a preferred embodiment of the present invention, the receiving section of the
cover is defined by guide walls arranged on the cover in a manner to be opposite to each
other. The guide walls may be respectively provided on a lower portion thereof with hook-like
projections in a manner to be opposite to each other and partially cover a lower
surface of the erasure prevention member, resulting in preventing the erasure prevention
member from being removed from the cover.
In a preferred embodiment of the present invention, the erasure prevention
member is provided on upper and bottom surfaces thereof with an operation element and
a discrimination indication portion in a manner to be projected therefrom, respectively.
The cover may be provided at a portion of a top wall thereof defined between the guide
walls with an operation hole corresponding to the operation element.
In a preferred embodiment of the present invention, the disc cartridge further
includes a discrimination member, removably provided on the casing, for indicating that
takeout of the disc-like medium has not been carried out and a release projection
provided on the cover so as to be abutted against the discrimination member.
In a preferred embodiment of the present invention, the discrimination member
is formed in a manner to be integral with the lower casing member while being partially
separated from the lower casing member through a ring-like slit formed between the
discrimination member and the lower casing member and connected to the lower casing
member through a thin-wall connection arranged therebetween. The discrimination
member is provided thereon with a projection, wherein the projection of the discrimination
member is arranged in proximity to the connection so as to be abutted against the release
projection, resulting in the discrimination member being removed from the lower casing
member and discharged outwardly of the casing due to abutment of the release projection
against the projection of the discrimination member caused during the sliding movement
of the cover.
In a preferred embodiment of the present invention, the release projection is
shaped in the form of an arcuate rib and connected to an outer surface of one of the
guide walls formed on the cover for defining the receiving section for receiving the
erasure prevention member therein.
In a preferred embodiment of the present invention, the upper and lower
casing members are formed with substantially the same outer configuration and the other
casing member opposite to the one casing member on which the cover is arranged is
formed at a portion of an inner surface thereof opposite to the cover with a flat shape.
In a preferred embodiment of the present invention, the cover and the one
casing member are formed at respective edge portions thereof abutted against each
other with stepped fit surfaces.
In a preferred embodiment of the present invention, the shutter includes a
slider structure for slidably guiding the shutter and an elastic member for urging the
shutter in a direction of closing the openings.
BRIEF DESCRIPTION OF THE DRAWINGS
These and other objects and many of the attendant advantages of the present
invention will be readily appreciated as the same becomes better understood by
reference to the following detailed description when considered in connection with the
accompanying drawings, in which like reference characters designate like or
corresponding parts throughout; wherein:
Fig. 1 is an exploded perspective view showing an embodiment of a disc
cartridge according to the present invention; Fig. 2 is an exploded perspective view showing a casing for the disc cartridge
shown in Fig. 1, viewed from a bottom side of the casing; Fig. 3 is a fragmentary exploded perspective view showing an inside of an
upper casing member; Fig. 4 is an enlarged vertical sectional view taken along line IV-IV of Fig. 3; Fig. 5 is an enlarged vertical sectional view taken along line V-V of Fig. 3; Fig. 6 is a fragmentary enlarged bottom view showing the upper casing
member and a cover; Fig. 7 is a vertical sectional view taken along line VII-VII of Fig. 6; Fig. 8 is a fragmentary plan view showing the cover; Fig. 9A is a fragmentary vertical sectional view showing an erasure prevention
member during assembling thereof into the casing; Fig. 9B is a fragmentary vertical sectional view showing the erasure prevention
member after completion of assembling thereof into the casing; Fig. 10 is a fragmentary exploded perspective view showing an inside of an
upper casing member of another embodiment of a disc cartridge according to the present
invention; Fig. 11 is a fragmentary enlarged bottom view showing the upper casing
member and a cover; Fig. 12 is a vertical sectional view taken along line XII-XII of Fig. 11; Fig. 13 is a vertical sectional view taken along line XIII-XIII of Fig. 11; Fig. 14 is a fragmentary plan view showing the cover; Fig. 15 is a fragmentary perspective view in section showing a discrimination
member incorporated in the casing; Fig. 16A is a fragmentary vertical sectional view showing the discrimination
member right before movement of the cover; Fig. 16B is a fragmentary vertical sectional view showing the discrimination
member during movement of the cover; and Fig. 16C is a fragmentary vertical sectional view showing the discrimination
member after opening of the cover.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Now, a disc cartridge according to the present invention will be described
hereinafter with reference to the accompanying drawings.
Referring first to Figs. 1 to 9B, an embodiment of a disc cartridge according to
the present invention is illustrated. A disc cartridge of the illustrated embodiment is
adapted to receive an optical disc-like medium therein. The disc cartridge includes a
casing formed by joining an upper casing member 1 and a lower casing member 2 to
each other. The disc cartridge also includes a disc-like medium 10 rotatably received in
the casing so as to act as an information medium. The disc-like medium 10 may be either
a both-sided recordable/reproducible disc or a one-sided recordable/reproducible disc.
The casing is formed with apertures or openings such as head insertion holes 11 and 21
through which a head of a recording/reproducing unit is inserted into the disc cartridge,
drive shaft insertion holes 12 and 22 through which a drive shaft of the unit is inserted
thereinto, and the like. The disc cartridge further includes a shutter 4 for selectively
opening or closing the openings, which shutter is slidably arranged on a slide area 5
provided on an outer surface of the casing in a manner to be depressed from a level of
the outer surface. The shutter 4 includes an upper plate 41, a lower plate 42, and a
connection plate 43 through which the upper plate 41 and lower plate 42 are connected to
each other and formed with a substantially U-shape in section. The shutter 4 has first and
second sliders 6 and 7 for slidably guiding the shutter 4 and an elastic member or spring
8 for constantly urging or forcing the shutter 4 in a direction of closing the openings
incorporated therein. In the illustrated embodiment, one such first slider 6 is arranged to
slide while being engaged with first guide sections or guide projections 91 provided on the
upper and lower casing members 1 and 2, and a pair of such second sliders 7 are
forcedly held at opposite ends of the first slider 6 by means of the spring 8 so as to
interpose the first slider 6 therebetween and arranged so as to slide while being engaged
with second guide sections or guide grooves 92 provided on the upper and lower casing
members 1 and 2. The second sliders 7 are also arranged so as to be pressedly abutted
against respective stoppers or projections provided on the casing along the opposite ends
of the openings formed at a central portion of a front side of the casing, resulting in the
shutter 4 in being operated to open both directions.
The casing is formed on a side surface thereof opposite from a side surface
thereof on which the shutter 4 is arranged with a takeout opening 13 which permits the
disc-like medium 10 to be taken out of the casing therethrough. The takeout opening 13
may be formed in any one of the upper and lower casing members 1 and 2 of the casing.
In the illustrated embodiment, the opening 13 may be formed in the upper casing member
1. Also, the casing is provided thereon with a disc-like medium takeout cover 3 in a
manner to be movable and more specifically both slidable and pivotable, to thereby open
and close the takeout opening 13. The takeout cover 3, as shown in Fig. 2, is provided
with a receiving section 15 in which an erasure prevention member 14 is received. The
erasure prevention member 14 is slidably held in the receiving section 15, resulting in the
disk-like medium 10 being selectively set in a "recordable" state or an "unrecordable"
state.
The erasure prevention member receiving section 15 is defined between guide
walls 16 arranged on the cover 3 in a manner to be opposite to each other. The cover 3
is provided on a portion of a top wall thereof interposed between the guide walls 16 with
an operation opening 17 as shown in Figs. 7 and 8. The guide walls 16 are provided on a
lower portion thereof with respective hook-like projections 18 in a manner to be opposite
to each other so as to partially cover a lower surface of the erasure prevention member
14, to thereby prevent the erasure prevention member 14 from being removed or
detached from the receiving section 15.
The erasure prevention member 14 is provided on a top surface thereof with
an operation element 141 and on a bottom surface thereof with a discrimination indication
portion 142 in a manner to be projected therefrom, to thereby facilitate both operation of
the member 14 and discrimination of a direction or position thereof.
In the illustrated embodiment, the cover 3 is provided on opposite sides thereof
with support shafts 30 and pivotally and slidably arranged through the support shafts 30
on a portion of one of the upper and lower casing members 1 and 2, for example, on a
side of the upper casing member 1 opposite from the side surface of the casing on which
the shutter 4 is arranged and in proximity to ends of the side. The erasure prevention
member 14 for selectively setting the disc-like medium 10 in a "recordable" state or an
"unrecordable" state is movably arranged in the cover 3. The hook-like projection 18 is
provided on the lower portion of each of the guide walls 16 for guiding movement of the
erasure prevention member 14, to thereby prevent the erasure prevention member 14
from being removed or detached from the cover 3 when the disc cartridge is both in a
normal position and an inverted position or turned upside down while the cover 3 is
opened. In the illustrated embodiment, the hook-like projections 18 each have a bottom
surface inclined and the guide walls 16 are kept from being connected to both an outer
peripheral wall of the cover 3 and an arcuate wall 19 for guiding an outer periphery of the
disc-like medium 10, so that the guide walls 16 may be readily elastically deformable in an
outward direction when the erasure prevention member 14 is incorporated into the
receiving section 15 of the cover 3 as shown in Figs. 9A and 9B.
The support shafts 30 of the cover 3 are supported or slidably and pivotally
fitted in respective guide grooves 31 formed on opposite sides of the upper casing
member 1, resulting in ensuring both parallel displacement and pivotal movement of the
cover 3. This permits the cover 3 to be opened while being separated from the other
casing member or lower member 2. Opening of the cover 3 is carried out by first carrying
out parallel displacement of the cover 3 in a direction remote away from the shutter 4.
Then, the cover 3 is pivotally moved to open the takeout opening 13. In the illustrated
embodiment, an inner face of the lower casing member 2 opposite to the upper casing
member 1 on which the cover 3 is arranged is formed so as to have a flat surface free
from any projection, to thereby prevent the disc-like medium 10 from being caught by the
lower casing member 2 during withdrawal or takeout thereof from the casing through the
takeout opening 13 opened. Holding of the cover 3 during closing thereof is
accomplished by engagement between projections 32 provided on the opposite sides of
the cover 3 and recesses formed at the lower casing member 2, to thereby prevent
accidental opening of the cover 3. The holding may be carried out either lightly so as to
ensure ready opening of the cover 3 or firmly so as to ensure opening thereof with
difficulty by forcedly pressing both sides of the cover 3 to elastically deform it, depending
on applications thereof.
In the illustrated embodiment, the support shafts 30 are each formed at a distal
end thereof with a cylindrical shape and partially cut out so as to have a flat surface
formed on a part of an outer peripheral surface thereof and the guide grooves 31 are
each formed with a shape which permits a respective one of the support shafts 30 to slide
while the cut-out flat surface portion of the support shaft 30 is guided along a side surface
of the guide groove 31. The guide grooves 31 are each formed at one end thereof with a
circular hole 311 in which a corresponding one of the support shafts 30 of the cover 3 is
rotatably fitted, resulting in the cover 3 being pivotable. Such displacement and pivotal
movement of the cover 3 permit the disc-like medium 10 to be selectively taken out from
the casing as desired. Opening of the cover 3 may be carried out in any other suitable
manner such as rotation thereof about an end of the upper casing member 1, mere
sliding thereof or the like.
The shutter 4 is fixed on the first slider 6. For example, the shutter 4 may be
slid between a closing position at which the openings of the casing are closed and an
opening position at which the openings are opened while being guided by the guide
projections 91 and guide grooves 92 of an inner surface of the casing. The shutter 4 may
be made of polyacetal resin by injection molding and formed with a substantially U-shape
in section.
In Figs. 1 to 9B, reference numeral 143 designates an elastic arm, 23 is a label
area, 24 is a shutter holder, and 25 and 26 are stepped fit surfaces formed at respective
edge portions of the cover 3 and the upper casing member 1 which are abutted against
each other, to thereby prevent dust from entering the casing during storage of the disk
cartridge.
As described above, the disc cartridge of the illustrated embodiment is so
constructed that the casing is formed on the side surface thereof opposite from the
shutter 4 with the takeout opening 13 which permits the disc-like medium 10 to be taken
out of the casing therethrough; the cover 3 is slidably and pivotally arranged on the casing
for opening and closing the takeout opening 13 in such a manner that one of the upper
and lower casing members 1 and 2 is provided with the guide grooves 31 in which the
respective support shafts 30 of the cover 3 are slidably and pivotally fitted, to thereby
permit the cover 3 to be selectively opened while being separated from the other of the
upper and lower casing members 1 and 2; the cover 3 is provided with the receiving
section 15; and the erasure prevention member 14 is slidably held in the receiving section
15 of the cover 3. Such construction permits takeout and insertion of the disc-like
medium 10 with respect to the casing to be readily and safely carried out and ensures
operation of the cover 3 with increased reliability. Also, such construction permits the
disc-like medium 10 to be selectively and repeatedly set in an erasure prevention state or
a recordable state and prevents removal of the erasure prevention member 14 from the
casing during the opening or closing operation of the cover 3. Further, such construction
facilitates takeout and insertion of the disc-like medium 10 with respect to the casing while
ensuring increased reliability in operation of the disc cartridge.
Referring now to Figs. 10 to 16C, another embodiment of a disc cartridge
according to the present invention is illustrated. A disc cartridge of the illustrated
embodiment is so constructed that a cover 3 slidably and pivotally mounted on an upper
casing member 1 is provided thereon with a release projection 34 and a lower casing
member 2, as shown in Figs. 11 to 15, is removably or detachably mounted thereon with a
discrimination member 27 so as to be abutted against the projection 34 as shown in Figs.
15 to 16C. More particularly, the discrimination member 27 is adapted to detect whether
the cover 3 has been opened in the past, or to indicate that takeout of a disc-like medium
10 has not been carried out, and is arranged on a portion of the lower casing member 2
opposite to the cover 3. The discrimination member 27 is provided on an inside thereof
with a projection 29 and includes a connection 28 through which the discrimination
member 27 is connected at a part thereof to the lower casing member 2, resulting in the
discrimination member 27 being removed from the lower casing member 2 at the
connection 28. For this purpose, the connection 28 is preferably formed to have a
reduced thickness to facilitate removal or separation of the discrimination member 27
from the lower casing member 2. The discrimination member 27 thus constructed may be
provided on the lower casing member 2 by integrally forming the discrimination member
27 on the lower casing member 2 in such a manner that a ring-like slit is provided
between the discrimination member 27 and the lower casing member 2 while leaving the
thin-wall connection 28 therebetween. Thus, the discrimination member 27 may be
connected to the lower casing member 2 through only the thin-wall connection 28. The
projection 29 of the discrimination member 27 which is adapted to be abutted against the
release projection 34 is arranged in proximity to the thin-wall connection 28, to thereby
ensure that the discrimination member 27 is positively discharged outwardly of the casing
when it is removed or separated therefrom due to abutment of the release projection 34
against the discrimination member 27 and more particularly the projection 29 of the
member 27, which abutment is caused during the sliding movement of the cover 3, as
shown in Figs. 16A to 16C.
The release projection 34 is arranged on a portion of the inner surface of the
cover 3 opposite to the discrimination member 27 and shaped in the form of a rib having
a pillar-like shape which is, for example, arcuate in section. Also, the release projection
34 is arranged so as to be positioned in proximity to the projection 29 of the discrimination
member 27 of the lower casing member 2 when the cover 3 is kept closed. Further, the
release projection 34 may be arranged so as to be connected to an outer surface of one
of guide walls 16 formed on the cover 3 so as to define a receiving section 15 for
receiving an erasure prevention member 14 therein. Such arrangement of the release
projection 34 facilitates detection of the discrimination member by the release projection
34.
The remaining part of this embodiment may be constructed in substantially the
same manner as the first embodiment described above.
For opening of the cover 3, it is required to move or slide the cover 3 in a
direction remote away from the shutter 4. This may be realized by forming each of the
guide grooves 31 of the upper casing member 1 to have a width increased at a rear end
thereof, for example, in the shape of a circular hole 311 and forming each of the support
shafts 30 of the cover 3 into a partially cut-out cylindrical shape, as shown in Fig. 5. Such
formation of the guide grooves 31 and support shafts 30, when the cover 3 is to be
opened, permits the cover 3 to be initially moved or slid in the rearward direction. Then,
the cover 3 is permitted to be pivotally moved after the support shafts 30 reach the
respective rear circular holes 311 of the guide grooves 31.
At the time of the first opening operation of the cover 3 to take out the disc-like
medium 10 from the casing, the pillar-like release projection 34 forcedly presses the
projection 29 of the discrimination member 27 of the lower casing member 2 during
sliding movement of the cover 3. Such an action of the release projection 34 permits the
discrimination member 27 to be bent about the connection 28 and finally removed from
the lower casing member 2, followed by outward discharge of the discrimination member
27 from the casing. Thus, when a user is to merely carry out takeout of the disc-like
medium 10, the discrimination member 27 is automatically operated without any specific
operation thereof, to thereby eliminate a failure to change the state of the discrimination
member 27.
Thus, the above-described construction of the illustrated embodiment permits
a user to carry out takeout of the disc-like medium 10 without a necessity of operating the
discrimination member 27, to thereby eliminate wrong use of the discrimination member.
In addition, the disc cartridge of the illustrated embodiment may be so
constructed that the upper and lower casing members 1 and 2 are formed with
substantially the same outer configuration. Furthermore, as the support shafts 30 and the
guide grooves 31 are correlative to each other, they may be transposed without a change
in function.
While preferred embodiments of the invention have been described with a
certain degree of particularity with reference to the drawings, obvious modifications and
variations are possible in light of the above teachings. It is therefore to be understood
that within the scope of the appended claims, the invention may be practiced otherwise
than as specifically described.